In the House, Republican Rep. Scott Rigell of Virginia is asking colleagues to sign a letter to Obama that urges him to reconvene Congress and seek approval for any military action. And in the Senate, even some who support punishing the Syrian government for launching alleged chemical weapons attacks are joining the call for the president to first gain Congress' approval.
"Engaging our military in Syria when no direct threat to the United States exists and without prior congressional authorization would violate the separation of powers that is clearly delineated in the Constitution," Rigell's letter argues.
A copy was obtained by The Associated Press on Tuesday.
To make their case, lawmakers are citing the 1973 War Powers Resolution. Passed after President Richard Nixon's secret Vietnam War-era operations, the law reaffirmed Congress' constitutional responsibility to declare war and put a 60-day time limit on the president's ability to take unauthorized, emergency military action. Since then, commanders-in-chief of both parties have maintained that the resolution is unconstitutional and have regularly disregarded it.
The Obama administration appears likely to use force in the coming days in response to reports last week of a large-scale gas attack by Syrian President Bashar Assad's forces in the Damascus suburbs. At least 100 people died.
Speaking to reporters Monday, Secretary of State John Kerry said evidence of such an attack was "undeniable" and that intelligence strongly pointed to Assad's government — a claim the Syrian leader called "preposterous." Kerry said that international standards against chemical weapons "cannot be violated without consequences," outlining the clearest justification yet for U.S. military action, most likely coming through sea-launched cruise missiles on regime targets.
After a decade of costly and deadly fighting in the Muslim world, Americans strongly oppose any new U.S. war in the region. Opinions in Congress are mixed as well. Republicans are split between hawks and tea party isolationists. Democrats are divided between advocates of humanitarian intervention and those who fear that even limited action risks sucking the United States into another conflict.
Despite the divides, legislators of varying political hue are trying to reassert what they claim is their power to authorize the use of force.
Sen. Tim Kaine of Virginia, a former Democratic Party chairman, said the Assad regime must be held accountable for its indiscriminate violence and "despicable" chemical attacks. But he urged that proper procedures are followed.
"Absent an imminent threat to United States national security, the U.S. should not be engaged in military action without congressional approval," Kaine said. Sen. Bob Corker of Tennessee, the top Republican on the Foreign Relations Committee, has made a similar argument.
Sen. John Cornyn, R-Texas, asked only that Obama present his case to the American people and consult with Congress. "He needs to explain what vital national interests are at stake and should put forth a detailed plan with clear objectives and an estimated cost for achieving those objectives," he said.
That doesn't seem near enough for tea party favorite Rep. Justin Amash, R-Mich., who has issued a series of tweets arguing that unauthorized strikes against Syria would be unconstitutional and illegal. He is putting pressure on leadership in his own party to call Congress back into session for a debate and vote before any such action occurs.
Lawmakers are scheduled to return from a five-week recess on Sept. 9.
It's unclear what impact all the activity will yield. When the U.S. acted with allies against Libyan dictator Moammar Gadhafi two years ago, Obama maintained military operations for more than three months without congressional authorization. He said the U.S. wasn't violating the War Powers Resolution because Americans were supporting a NATO-led operation and weren't engaged in full-blown hostilities. Despite criticism from mainly Republican lawmakers, Obama suffered no serious repercussions.
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